PROJECT SUMMARY/ABSTRACT Obesity is a major public health problem that disproportionately affects rural men1 and promotes the development of chronic conditions such as diabetes, cardiovascular disease, arthritis, and cancer.2 This study proposes to evaluate a 3-month mobile self-monitoring application (app) with Wi-Fi scale and text messaging intervention (MT+: mobile technology plus) for achieving weight loss in overweight and obese rural men. Weight loss interventions for rural men constitute a gap both in the literature and current NIH-NINR research portfolios. Using a pragmatic randomized controlled trial and community engaged research (CEnR) approaches, this study aims to: 1) determine the feasibility and acceptability of a smart phone self-monitoring app (Lose-It Premium) plus SMS text-based and daily weighing via Wi-Fi scale intervention (MT+) for achieving weight loss, 2) determine preliminary efficacy of MT+ to a comparison group receiving only a self- monitoring app (Lose-It Basic) (MT) in achieving the outcomes of weight loss (kg and % body weight-primary) and improved dietary and physical activity (PA) behaviors (secondary) at 3 and 6 months post-baseline, and 3) determine quantitative and qualitative indicators of community capacity to support a contextually relevant weight loss intervention. Eighty men (ages 40-65) with BMI of 28-45 kg/m2 will be randomly assigned (1:1 ratio) to intervention group (MT+) or comparison group (MT). Men will complete baseline assessments (weight (kg), % body fat, BMI, height, blood pressure (BP), health history, dietary intake, PA intensity) and receive orientation to the mobile technologies (Lose-It app features, SMS, Wi-Fi scale). Men will track their dietary intake, PA, and weight on the Lose-It app for 12 weeks. After the 3-month intervention, post-measure assessments (weight-kg, % body fat, BMI, dietary intake, PA frequency/intensity, and technology usability surveys) will be collected at 3 and 6 months post-baseline. At 6 months post-baseline, two groups (n=8 each) of MT+ completers will be purposively selected to share their perceptions of the intervention efficacy in evaluative focus groups. A community advisory board (CAB) comprising local leaders within the men?s social network, together with investigators and rural student nurses will guide community outreach efforts for study recruitment, implementation, and evaluation. Study findings will be evaluated with the CAB to inform local dissemination, future intervention revision, and determination of community capacity for support of a larger clinical trial.